This invention relates to a fuel pump, fuel tank arrangement for an internal combustion engine and more particularly an improved arrangement of fuel pump and fuel tank and fuel supply system for an engine.
In many applications for internal combustion engines, fuel is supplied to the engine from a remotely located fuel tank. In addition, fuel may be returned back to the fuel tank for a variety of reasons, such as if there is a pressure regulator in the fuel supply side of the system. Pressure is regulated by returning excess fuel back to the fuel tank. Thus, there are necessitated a number of connections between the fuel tank and the fuel supply system.
The desirability of positioning the fuel pump within the fuel tank is also well known. Such placements permit ease of priming and also provides some silencing for the operation of the fuel pump. If the fuel line connections for the return line and the opening through which the fuel pump is inserted in the fuel tank are positioned at a low level in the fuel tank, this means that the fuel tank must be drained before the elements can be serviced. This is clearly a disadvantage.
Also, the use of plurality of separate connections to a fuel tank gives rise to the increased possibility of leakage and also more complex fuel tank constructions.
It is, therefore, a principal object of this invention to provide an improved fuel pump return, line system for a fuel tank for an engine wherein the fuel pump may be removed and serviced without necessitating draining of the fuel from the fuel tank.
It is a further object of this invention to provide an improved fuel pump return line arrangement wherein the fuel pump and return line are all formed in a common assembly which closes a single opening in the upper portion of the fuel tank so as to minimize the number of connections and also to facilitate servicing without draining the fuel tank.
It has been proposed in automotive applications to provide a fuel pump that is inserted through a top wall of the fuel tank so as to permit removal of the fuel pump without draining the fuel in the fuel tank. Such top wall mounting arrangements, however, have some disadvantages, particularly with certain types of motor vehicles such as a motorcycle.
It is, therefore, a still further object of this invention to provide an improved fuel tank, fuel pump arrangement wherein the fuel pump may be inserted into the fuel tank through an opening in the fuel tank without necessitating draining of the fuel tank and also without having the fuel pump pass through an opening in a top wall of the fuel tank.
As noted above, there are certain problems in conjunction with the fuel tank and fuel system component layouts particular to certain types of motor vehicles. For example, motorcycles are extremely small and compact and frequently the fuel tank is positioned in close proximity to and above the engine. However, if a pressure system is employed such as that using a fuel injection system and pressure regulation, the height differences of the various components can give rise to problems in adequate pressure control and component placement. In addition, it is desirable to permit ease of servicing of the components for the fuel tank and the fuel tank mounting of a motorcycle, as noted above, is quite different from that in an automobile. Frequently the fuel tank is positioned directly in front of the rider""s seat and above the engine and thus can give rise to problems since the fill neck is in the top of the fuel tank and may cover substantially all of the exposed upper portion of the fuel tank.
It is, therefore, a still further object of this invention to provide an improved fuel pump, fuel tank arrangement particularly adapted for use in a motorcycle.
A first feature of the invention is adapted to be embodied in a fuel tank, fuel pump arrangement for supplying fuel to an internal combustion engine. The arrangement includes a fuel tank for containing fuel and which has upper wall area that is disposed above the area wetted by the fuel when the fuel tank is at least less than half full. An opening is formed in the upper wall area and a combined fuel pump, fuel return assembly closes this opening. This assembly comprises a mounting plate that is adapted to be affixed to the upper wall area, a fuel pump for pumping fuel attached to the plate and a return fitting for receiving an external conduit for returning fuel to the fuel tank from the engine fuel system.
Another feature of the invention is also adapted to be embodied in a fuel tank, fuel pump arrangement for supplying fuel to an internal combustion engine. In accordance with this feature of the invention, the arrangement includes a fuel tank for containing fuel and having at least one side wall with an upper wall area disposed above the area wetted by the fuel in the tank when the tank is at least less than half full. An opening is formed in this upper wall area and a fuel pump is affixed into this opening for pumping fuel and for closing the opening.
A further feature of this invention is adapted to be embodied in a motorcycle having a frame assembly which dirigibly supports a front wheel. A rear wheel is suspended from the frame assembly and an engine carried by the frame assembly drives the rear wheel. A fuel tank is provided for supplying fuel to the engine and is supported by the frame assembly. The fuel tank has a portion that extends above the frame assembly and an opening is formed in this upper fuel tank portion. A combined fuel pump closure assembly closes the opening and pumps fuel from the fuel tank to the engine.